Development of 200 keV polarized electron gun

A 200 keV polarized electron gun system with a load lock mechanism has been developed to produce the high-intensity and low-emittance beam required by Japan Linear Collider. The construction of this system has been completed and the performance tests are in progress. Up to now, DC high voltage of 150 kV could be successfully applied to the accelerating electrodes with an extremely low dark current of <0.1 nA.